Consider a packaging facility that packages some product delivered to the facility by trucks. Every day, trucks arrive evenly from 9am to 5pm and unload 80 units of unpackaged product per hour at a small warehouse attached to the packaging facility. The assembly process involves two stations that take items from the warehouse and pack them. It takes a station 2 minutes to package each item. The packaged items are shipped out immediately to retail stores. The warehouse can hold up to 100 units of the product. Once the warehouse is full, the trucks have to hold the items and wait its turn to unload items it carries. The facility continues to run until all the items delivered in a day are all packaged.

1. What is the maximum number of items that are waiting on the trucks at any given time?

2. What is the average waiting time of a truck that has to wait?

3. What is the average flow time of an item?

4.